Electric signaling system.



E. W. ADAMS.

ELECTRIC SIGNALING SYSTEM.

APPLICATION FILED OCT. 2.1916.

Patented Nov. 6, 1917'.

2 I 3 I 1 vemfor' 476 W. Adams by W W use of tuned reeds as a means particular frequency,

' To all whom it may concern:

UNITED STATES PATENT OFFICE.

upon. w.

' comm ELECTRIC SIGNALING srsrnm.

ADAMS, 01 EAST ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECT-BIG INCORPORATED, 01' NEW YORK, N. Y., A CORPORATION OF NEW YORK.

SpeQlflcation of Letters Patent.

Patented Nov. 6, 191 '7.

Application filed October 2, 1916. Serial N 0. 123,872.

Be it known that I, EDGAR W. ADAMS, a citizen of the United States, residing at East Orange, in the county of Essex and State of New Jersey, have invented certa n new and useful Improvements in Electric Signaling Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to electric signaling systems and more particularly to means in a telephone system for transmitting 1ntelligence from one operator to another.

In certain telephone systems, it is necessary for an operator to cause a visual indication of a telephone number to be displayed before another operator. Heretofore, this has been accomplished through the use of rather complicated circuits comprising a great number of relays and signaling lamps, with all the disadvantages arising from such a multiplicity of delicate apparatus.

- The object of this invention is to provide a simple and improved indicating device and means for operating the same.

A feature of the invention relates to the for indicating a telephone number. Devices employing tuned reeds have heretofore been used for indicating certain characteristics of electric current, such, for instance, as the frequency of a source of alternating current. In accordance with a related feature of the invention, means are provided to continue the indication at will even after the original energizing current has ceased to flow.

In thedrawing, the portion to the left of the broken line represents apparatus at one operators position, whereby she may send characteristic impulses over a connecting circuit to another operators' position. The portion to the right of the broken line rep resents the apparatus at the second operators position, comprising a device to receive the impulses from the connecting circuit and translate them into a visual indication.

The first operators position is equipped with a bank of keys arranged according to the decimal system for sending out .impulses corresponding to the digits of a telephone number, each key for sending out the numeral 1 being supplied with current of a each key for sending out the impulses corresponding to the numeral 2 being supplied with current of another definite frequency, and so on.

.mittently closes a contact at a rate '100 moves under the control of its The operator selects certain keys,'for instance, in the case assumed for purposes of illustration, 2 in the thousands row, 6 in the hundreds row, 4 in the tens row, and 5 in the units row, the number which it is desired to indicate being 2645. A sequence switch of well-known construction, such as is shown in patent to Reynolds and Baldwin No. 1,127,808, is provided to cause the current impulses to flow first from the thousands key 2, and in turn from the hundreds key 6, the tens key 4- and the units key 5.

his train of impulses is received at the second operators position through an alternating current relay by an indicating device somewhat similar to the well-known Hartman andBraun frequency meter or as disclosed in the British Patent No. 21,347 of 1906. It consists of a set of tuned reeds, each reed being tuned to a separate and distinct frequency of alternating current. The set of reeds is energized by a single magnet which causes the one reed which is tuned to the particular frequency of alternating current being transmitted to vibrate with an amplitude which makes its end distinctly noticeable. ,The vibration or" this reed interequal to its own frequency, and thereby sets up an intermittent current in its energizing coil exactly in tune with this reed. The'reed will, therefore, continue to vibrate until the supply of this current is cut ofi.

he invention may best be understood by a detailed description of the operation.

Let us assume that the cated at O has been taken for use on a call by a certain subscriber to the subscriber whose number is 2645. The operator, upon learning the number of the called line, presses the keys 1, 2, 3 and 4, which remain in the actuated position until released in any Well-known manner. When the number has thus been set up, she presses the startkey 5. We will assume, furthermore, that the sequence switch 100 has, in coiiperating with other apparatus (not shown) to bring the call to the point just described, been driven into position 3. When the operator presses the key 5, therefore, a circuit is completed from ground, key 5, sequence switch contact 101, winding of the motor-magnet 100, battery and ground. Sequence switch contact A into the thirteenth position.

cord circuit indi is so tuned. Reed No. 2 will, therefore, be-

- circuit t rough hundreds key Asthe se uence switch passes from position 3 and into position 5, contact 108 is closed, thus connecting the sending device to one side of the cord circuit 0, extending through telephone line L to the second operators position. It may be assumed, for example, that the connecting circuit 0 has been extended to an idle operators position by means of a selector or distributing switch the brushes of which are indicated at 6 and 6 and the terminals at 7 and 7'.

In positions '5 and switch 100, a circuit is completed from ground, alternating-current generator deliv-' ering current at 20-cycles per second, contacts of key 1, sequence switch contact 103, sequence switch 102, line D, brush 6, terminal 7, alternating-current relay 8, sequence switch contact 201, winding of magnet 9, sequence switch contact 202, to ground. We will assume in this case that the second reed is tuned to 20-cycles per second, and that no other reed of the ten in the thousands row in to vibrate with such an amplitude that it becomes distinctly noticeable among the rest of its companion reeds.

Each reed is rovided with an auxiliary contact which, uring the vibration of the reed, sets up an intermittent circuit which in the case of the reed illustrated at 10 may be traced from ground, battery, contact of reed 10, winding of magnet 11, sequence switch contact 202, to ground. Since the reed 10 causes an intermittent current to flow through the magnet 11 of the frequency to which it is tuned, it will continue to vibrate until this circuit, just described, is broken. I q

The flow of current through alternatingcurrent relay causes it to attract its armature, whereupon a circuit is established from ground, armature and contact: of relay 8, sequence switch contact 203, sequence switch motor-magnet 200, battery andv ground. Sequence switch 200 moves under control of its contact A into the second position. It should be noted here that the contact of relay 8, which is slow acting, will be closed only a sufiicientlength of time to cause the sequence switch 200 to move forward one position.

It will be remembered that se uence switch 100 is steadily moving forwar it passes out of position 6, the energizing circult through thousands key 1 is opened, and when it asses into position 7, an energizin This may be traced from ground, alternating-current generator deliverying 60-cycle current, contacts of key 2, sequence switch contact 104, sequence switch contact 102, line L, brush 6, terminal 7 alternating-current relay 8, sequence switch contact 204, winding of magnet 12, sequence switch contact 202, to

6 of the sequence 2 is close ground. In this case, the sixth reed is tuned to 60-cycles andwill, therefore, begin to vibrate, and continue in its vibration in the manner previously described in connection with the reed indicated at 10. A momentary closure of the contact of the armature of relay 8 closes the circuit heretofore described long enough to drive sequence switch 200 from position 2 to position 3.

As sequence switch 100 moves out of position 8 an energizing circuit through hundreds key 2 is broken, and as it passes into osition 9, an ener izing circuit through tens ey 3 is closed. his may be traced from ground, alternating-current generator delivering current of 40-cycles per second, contacts of key 3, sequence switch contact 105, sequence switch contact 102, line L, brush 6, terminal 7 alternating current relay 8, sequence switch contact 205, winding of magnet 13, sequence switch contact 202 to ground. The fourth reed responds to this energizetion and begins to vibrate. Again the contact of relay 8 will be closed long enough to drive the sequence switch 200 from position 3 to position 4.

As sequence switch 100 moves out of position 10, the energizing circuit through key 3 is broken, and as it moves into position 11, an energizing circuit through the units key 4 is closed. This may be traced from ground, alternating-current generator delivering current of 50-cycles er second, contacts of key 4, sequence switch contact 106, sequence switch contact 102, line L,

brush 6, terminal 7, alternating-current relay 8, sequence switch contact 206, winding of magnet 11, sequence switch contact 202 to ground. The fifth reed, No. 10, responds to this 50-cycle-current and begins to vibrate. Relay 8 attracts its armature long enough to drive sequence switch 200 from position4 to position 5.

11 position 5 the four indicate the number 2645, will continue their vibration, and the operator, noting the number, sets up the connection accordingly. When the operator has no more use for the indication, she presses key 14. This completes a circuit from ground, contacts of ey 14, sequence switch contact 207, winding of sequence switch motor-magnet 200, battery, to ground. Sequence switch 200 is driven under control of its contact A from the fifth position into another position where it may perform additional functions if desired. As the sequence switch p out of position 5, contact 202 will be opened and the energizing circuit for each of the reeds will be broken at this point, whereby they will come to rest and the visual indication will cease.

As the sequence switch 100 reaches position 13, the circuit from the sendin device will be opened at contact 102, and e cord reeds, which thus circuit will be connected in thetrunk 1 through contacts 107 and 108 for talking rality of sets of purposes.

It should be noted that while ten alterhating-current generators are indicated delivering currents of ten, twenty, thirty and up to one hundred cycles, respectively, that any other device for generating electric currents of definite frequencies may be used. Moreover, the frequencies herein indicated do not form an essential part of this invention, it being understood that other he quencies may just ,as well be used, as long as the reeds at the indicating device are tuned accordingly.

What is claimed is:

1. 'An indicating device comprising a plutuned reeds arranged to give a visual indication while vibrating, means including a source of alternatin current for selectively setting one reed 0 each set in vibration, and-means including a,

source of direct current for causing such select' ely operated reed to continue in vibration.

2. In an electric signaling system, a transmitting station, a receiving station, a circuit extendlng between said stations, means for transmitting intelligence between said stations comprising at said transmitting station a plurality of sets of keys, a plurality of sources of alternating current of difierent frequencies, means for successively connecting each set of keys to said circuit, means at said receiving station for translating the impulses into a visual indication consisting of a plurality of sets of electromagnetically operable vibratin each element in a set being tuned to a different frequency of alternating current, and means for successively switching the sets of vibrating elements into connection with said circuit, said switchin device being arranged to operate in sync ronism with said connecting means.

3. In an electric slgnaling system, a transmitting station, a receiving station, a circuit extendmg between said stations and means for transmitting intelligence between said stations comprising means located at the transmitting station for selectively impressing alternating currents of different frequencies on said circuit, and means located atsaid receiving station for receiving and translating said alternating currents lnto a visual indication comprising sets of tuned reeds, each reed in a set being tuned to a different frequency, and means for causing such reeds as are selectively operated to continue in vibration after the energizing alternating current has ceased to flow.

4:. An indicating device comprising a set of tuned reeds arranged to give a visual indication while vibrating, means including a source of current for selectively setting one reed of such set in vibration, and independent means for causing such selectively operated reed to continue in vibration.

In witness whereof, I hereunto subscribe my name this 29th day of September, A. D.

EDGAR W. ADAMS.

elements, to respond 

